Railway traffic controlling apparatus



p 5, 1939. G. R. PFLASTERER 2,172,014

RAILWAY TRAFFIC CONTROLLING APPARATUS Fil ed Jan. 25, 1938 5 i 11" B 16.52, m 15 191 0 B 0 2 HDP TOR Gea ge 2.850%91 91 HIS ATTORN EY Patented Sept. 5, 1939 PATENT OFFICE RAILWAY TRAFFIC CONTROLLING- APPARATUS George R. Pfiasterer, Greenville, 'Pa., assignor to- The' Union Switch & Signal Company, Swissvale, Pa., a corporati on of Pennsylvania Application January 25, 1938, Serial No. 186,826

5 Claims.

My invention relates to railway traffic controlling apparatus, and particularly to apparatus of the type comprising interlocking systems having signals, such, for example, as Searchlight sig- -5 nals, with a mechanism cooperating with a lamp for displaying a main indication, and also with means for displaying a call-on indication. One feature of my invention is the provision of means for causing the call-on indication to be displayed in the event that the lamp for the main indication becomes burned out when the signal mechanism is in the position for displaying the main indication.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying my invention.

Referring to the. drawing, the reference characters I and la designate the track rails of a stretch of railway along which trafi'ic normally moves in the direction indicated by the arrow, and which rails are divided by insulated joints 2 to form a track section IT. A track circuit is provided for this section comprising a battery 3 connected across the rails adjacent the exit end of the section and a track relay ITR connected across the rails adjacent the entrance end of the section.

Located at the entrance end of section IT is an interlocking signal S, comprising a main mechanism m with which is associated a lamp e, and a call-on mechanism with which is associated a call-on lamp el. This signal, as here shown, is of the well-known searchlight type, but may be of any other suitable type in which a signal mechanism cooperates with a lamp for displaying a main indication. A signal of the Searchlight type is disclosed and claimed in Letters Patent of the United States No. 1,864,224, granted to Wesley B. Wells on June 21, 1932, for Light signals.

As shown in the drawing, each of the signal mechanisms m and 0 comprises a member mounted to oscillate between two extreme positions, and controlled by a winding 4 and by a permanent magnet or an electromagnet, not shown, so that, when winding 4 is energized, member 5 will move to one of its extreme positions or the other according as winding 4 is energized by current of normal or of reverse p0- larity. I have, however, shown means for energizing winding 4 of call-on mechanism 0 by current of only one polarity, and hence member 5 of mechanism 0 will move to only one of its extreme positions. Member 5 of each signal mechanism is biased to the middle position, in which it is shown in the drawing, and which it occupies when winding 4 is deenergized.

Member 5 of main mechanism m carries three roundels G, R and Y arranged to cooperate with signal lamp e in such manner that, when member 5 is in its middle position, roundel R is in front of lamp e, whereas when member 5 is swung to the left or to the right, roundel Y or roundel G, respectively, is placed in front of lamp e. Member 5 of call-on mechanism 0 is similar to member 5 of main mechanism m, except that only roundels Y and R move in front of lamp el. As shown in the drawing, each of the lamps e and el is above the corresponding roundels, but the lamps are shown in this location for purposes of illustration and it is to be understood that in actual practice the lamps are directly behind the corresponding roundels.

Main signal mechanism m operates a contact I4'I5 which is closed only when its member 5 occupies the Y position, and operates a contact I4-l6 which is closed when its member 5 occupies the G or R position. Mechanism m also operates a contact [1-18 which is closed only when its member 5 occupies the G position.

Energization of winding 4 of mechanism m is controlled by a manually controllable lever L and by track relay ITR, and also by a pole changing relay DE. The control of relay DR forms no part of my present invention, and has therefore been omitted from the drawing. Lamp 6, which cooper-ates with mechanism m, is constantly lighted by a circuit which includes the winding of a light-out relay E in series with lamp e. The contacts which are operated by mechanism m control a signal repeater relay HDP.

Energization of winding 4 of mechanism 0 is normally controlled by an auxiliary manually controllable device, here shown as a push button circuit controller P, as well as by lever L, when relay HDP is deenergized. If lamp e should burn out, winding 4 of mechanism 0 is controlled by a back contact of light-out relay E while relay HDP is energized. Lamp el, which cooperates with mechanism 0, is constantly lighted.

As shown in the drawing, all parts of the ap paratus are in the normal condition, that is, track section IT is unoccupied, and therefore relay ITR is energized; relay DR is energized; lever L and push button circuit controller P are in their normal positions; windings 4 of mechanisms m and c are deenergized, and hence members 5 are in the middle positions and relay HDP is deenergized; lamps e and el are lighted, causing a red indication to be displayed by lamp 6 in cooperation with mechanism in and also a red indication to be displayed by lamp el in cooperation with mechanism c; and relay E is energized.

When an operator desires to admit a train to section lT, he will move lever L to the right, thereby closing contact 6. Winding 4 of mechanism m will then be energized by current of normal polarity, passing from terminal B of a suitable source of current not shown in the drawing, through contact 6 of lever L, coductor I, contact 8 of relay I'IR, front point of contact 9. of relay DR, winding 4 of mechanism 121, and front point of contact ID of relay DR to terminal of the same source of current. Member will therefore move roundel G in front 'of'lampe, causing the green indication to .be displayed. If relay DR. were deenergized, winding 4. of mechanism m would be energized by current of reverse polarity flowing in a circuit which is the same as the circuit just traced as far as contact8 of relay ITR, thence passing through the back point of contact H] of relayDR, winding 4 of mechanism m, and back point of contact 9-. of relay DRv to terminal 0. Memberiof mechanism m would then move its roundel Y in front of lamp e, causing a yellow indication to be displayed.

When relay DR is energized, causing winding 4 of mechanism m tobe energized by current of normal polarity, relay HDP willbeenergized by a circuit passing from terminal B, through contact l4.l6 of mechanism m, contact IT!8 of mechanism 112, and the winding of relay HDP to terminal 0. If relay. DR were deenergized, causing winding 4. of mechanism in to be energized by current of reverse polarity, relay HDP would be energized by a circuit passing from terminal B, through contact I i-Idof mechanism m, and the winding of relay HDP to terminal 0.

If, now, a train passes signal S into section IT, relay ITR will become decnergized, causing its contact 8 to open the, circuit for winding. 6,; of mechanism 111 which is thereby deenergized, causing mechanism m to again cooperate with lamp e to display the red indication. With winding 4 of mechanism m deenergized, contacts l4- I5 and Hl8.of mechanism m will be open, and hence relay HDP will be deenergized.

I shall next assume thatthe operator desires to permit a second train to enter section IT while the firsttrain still occupies this section. To do this he will close circuitcontroller P in addition to lever contact 6,, thus completing a circuit for energizing windingd of mechanismc, this circuit passing from terminal B, through contact 6 of lever L, conductor circuit controller P, back point of contact l3 of relayI-IDP, and winding 4 of mechanism 0 to terminal 0. Lamp el, in cooperation with mechanism 0, will now display a yellow indication, while lamp 6,, in cooperation with mechanismm, displays a red indication,

I shall now assume that all parts of the apparatus are again in the normal condition, and that the; operator again energizes winding 4 of mechanism in by closing contact 6 .of lever L and thereby completing one of the circuits previously traced for winding 4 of mechanism m. With winding 4 of mechanism m energized, relay HDP will be energized by one of its circuits previously traced. I shall alsoassume that lamp e is burned out and hence relay E is deenergized.

A second circuit will therefore be completedfor' winding 4 of mechanism 0, this circuit passing from terminal B, through contact [2, of .relay E,

front point of contact l3 of relay HDP, and winding 4 of mechanism 0 to terminal 0. Lamp el, in cooperation with mechanism 0, will then display the yellow indication, while no indication is being displaced by mechanism m on account of lamp 6 being burned out. With the yellow indication being displayed by lamp 6! in cooperation with mechanism 0, a train approaching signal S is permitted to enter section IT without having to stop.

It follows that, with apparatus embodying my invention, if the lamp associated with the main mechanism of a signal of a type similar to the one shown in the accompanying drawing should burn out, an indication will be displayed by the call-on indication means which will permit a train to keep moving instead of having to stop at the signal when conditions are such that it is safe for the train to keep going. This provision is especially important as a means of avoiding the unnecessary stopping of heavy freight trains.

Although I have herein shown and described only one form of apparatus embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invenion.

Having thus described by invention, what I claim is:

I; In combination, a section of railway track, a signal mechanism, a lamp, manually controllable means and means controlled by traific conditions in said section for conditioning said. signal mechanism to cooperate with said lamp to display a first indication. for authorizing traffic movements into said section only ifsaid'section isunoccupied, a second signal mechanism, a second lamp, auxiliary manually controllable means for conditioning said second signal mechanism to cooperate with said second lamp to display a second indication for authorizing traffic movements into the, same section When said section is occupied; and means controlled by said firstsignal mechanism an-d by said'first lamp for conditioning said second signal mechanism to cooperate with said secondlamp to display said second indication if ,said first signal mechanism is conditioned for displaying said first indication but said first lamp is burned out.

2. In. combination, a section of railway track, a signal mechanism, a lamp, manually controllable means for conditioning said signal, mechanism to cooperate with saidlamp .to display a first, indication, 'for authorizing traffic movements into said section, a second signal mechanism, a second lamp, and means controlled by said. first. signal mechanism for energizing said second signal mechanism to cooperate with said second lamp-to. display a second, indication for authorizing traffic'movements in thesame sec- .tion if said first signal mechanism is conditioned for displaying said first indication but said first lamp is burned out,

3. In combination, a signal mechanism, a lamp, a circuit for constantly energizing said lamp, manually. controllable means for conditioning said signal mechanism to cooperate with said lamp to display a first indication, a second sig-. nal mechanism, a ,secondlamp, and a second circuit controlled by. said first signal mechanism and by said first,circuitforenergizing saidsec- 0nd signal mechanism to cooperate with said second lamp to display a second indication if said first signalmechanismis' conditioned/for. displaying said first indication but said first lamp is burned out.

4. In combination, a section of railway track, a signal mechanism, a lamp, manually controllable means for operating said signal mechanism to a given position to cooperate with said lamp to display a first indication for authorizing traffic movements into said section, and means controlled by said signal mechanism for displaying a second indication for authorizing traific movements into said secion if said signal mechanism is operated for displaying said first indication but said lamp is burned out.

5. In combination, a signal mechanism, a lamp, manually controllable means for operating said signal mechanism to a given position to cooperate with said lamp to display a first indication, a relay, means controlled by said signal mechanism in said given position for energizing said relay, auxiliary manually controllable means controlled in part by a back contact of said relay for displaying a second indication, and means controlled by a front contact of said relay and by said lamp for displaying said second indication if said lamp is burned out.

GEORGE R. PFLASTERER. 

